IMSBC Code

The International Maritime Solid Bulk Cargoes (IMSBC) Code was adopted by IMO Resolution MSC.268(85) and became mandatory under SOLAS Chapter VI, Part A on 1 January 2011, replacing the non-mandatory Bulk Cargoes (BC) Code. It applies to all ships carrying solid bulk cargoes other than grain (grain is covered by the International Grain Code). The Code establishes individual schedules for listed cargoes, defines three cargo groups, and sets out shipper obligations, testing methods, declaration requirements, and emergency procedures.

Solid bulk cargo incidents — particularly liquefaction-related capsizes — have caused numerous total losses and hundreds of seafarer deaths since the 1990s. The IMSBC Code is the primary instrument addressing this risk, but enforcement depends on accurate shipper declarations and robust verification by Masters and cargo surveyors.

Cargo groups

• Group ACargoes liable to liquefy

  Hazard: Liquefaction under vibration and moisture — loss of shear strength, free surface effect, potential capsize

  Examples: Iron ore fines, nickel ore, bauxite (since 2017 amendments), mineral concentrates, coal slurry, mill scale

  Key requirement: Shipper must provide a Moisture Content (MC) declaration and a Transportable Moisture Limit (TML) certificate from an accredited laboratory. MC must not exceed TML at time of loading. Master may conduct the can test or flow table test on representative samples.

• Group BCargoes possessing chemical hazards

  Hazard: Toxic gas emission, flammability, self-heating, corrosivity, oxygen depletion, or explosion risk

  Examples: Coal (self-heating, methane emission), direct-reduced iron (DRI), calcium hypochlorite, ammonium nitrate fertilisers, fishmeal, seed cake

  Key requirement: Entry into cargo holds or adjacent enclosed spaces is prohibited without gas-testing and a Permit to Enter. Some Group B cargoes also exhibit Group A behaviour — they are listed under both groups and must satisfy all requirements of each.

• Group CCargoes neither liable to liquefy nor possess chemical hazards

  Hazard: No specific chemical or liquefaction hazard — bulk physical hazards only (dust, abrasion, weight shift)

  Examples: Cement clinker, feldspar, granite, ilmenite, phosphate rock, salt, sugar (raw), wood chips

  Key requirement: Shipper's declaration of the cargo name, bulk density, stowage factor, and angle of repose. No TML certificate required. Ship must still ensure structural adequacy and adequate ventilation where relevant.

Individual schedule layout

Each cargo listed in the IMSBC Code has its own schedule, identified by the Bulk Cargo Shipping Name (BCSN). Schedules follow a standard layout with the following fields:

• Bulk Cargo Shipping Name (BCSN)

  The correct name for the cargo as it must appear on the shipping documents and the Master's declaration.

• Characteristics

  Physical state (solid, granular, powdery), colour, odour, bulk density range, angle of repose, and moisture content range.

• Hazards

  Group classification (A, B, both, or C) and specific hazard descriptions such as liquefaction potential, toxic gas emission, self-heating, or dust generation.

• Stowage and segregation

  Hold type required (ship type 1 or general), ventilation requirements (natural or mechanical), maximum stack height, segregation from other cargoes and from sources of heat or ignition.

• Weathertightness

  Whether the cargo must be protected from ingress of water during the voyage.

• Emergency procedures

  Emergency schedules referenced from the EmS Guide (e.g., F-A, S-P), medical first aid guide references, fire-fighting agent restrictions.

• Methods of testing

  Approved test procedures for determining TML (for Group A) or other cargo characteristics. References to ISO standards.

• Additional information

  Cleanliness of holds required, special loading or discharge precautions, pre-loading surveys, documentation to be carried on board.

Shipper's obligations and Master's rights

• Shipper's declaration — Before loading any solid bulk cargo, the shipper must provide the Master with a written declaration stating the BCSN, the Group classification, and the properties required by the schedule. For Group A cargoes, the declaration must include the Moisture Content (MC) of the cargo and a TML certificate issued within the preceding six months.
• Master's right to refuse — The Master has the right and the duty to refuse to load if the shipper cannot provide the required declaration, if the declared MC exceeds the TML, or if the cargo appears inconsistent with the declaration. This right is expressly preserved by SOLAS VI/2 and the IMSBC Code.
• Independent testing — The Master may request an independent test of representative samples from the cargo at any time before or during loading. Approved test methods include the Proctor-Fagerberg method, the flow table test, and the penetration test. The can test is a simple on-board screening tool only and does not replace laboratory TML determination.
• Unscheduled cargoes — If a shipper wishes to carry a cargo not listed in the IMSBC Code, the competent authority of the country of origin must issue a tripartite agreement (with the flag state and the receiving country) permitting carriage on specified conditions. This is the mechanism by which new cargoes are assessed before formal schedule adoption.

Amendment history

• MSC.268(85)2008 (in force 1 Jan 2011)

  Original adoption of the IMSBC Code as mandatory under SOLAS VI. Replaced the old BC Code. Established the three-group framework and schedule format.

• MSC.318(89)2011 (in force 1 Jan 2013)

  01-11 amendment cycle: revised schedules for nickel ore and iron ore fines following a series of casualties; introduced additional testing guidance.

• MSC.393(95)2015 (in force 1 Jan 2017)

  02-15 amendment cycle: bauxite added to Group A following incidents; updated schedules for coal and direct-reduced iron (DRI).

• MSC.462(101)2019 (in force 1 Jan 2021)

  03-19 amendment cycle: new and revised schedules; updated testing methods; guidance on cargoes not listed in the Code.

• MSC.500(105)2022 (in force 1 Jan 2024)

  04-23 amendment cycle: revised schedules for seed cake, fishmeal, and coal; new schedules for lithium-ion battery scrap and end-of-life batteries; enhanced guidance on sampling procedures and declaration requirements.

See also

• · IMSBC Group A — liquefaction in detail — TML, FMP, casualties, and loading plan implications.
• · International Grain Code — the companion code for grain in bulk under SOLAS VI Part C.
• · SOLAS — Chapter VI (Carriage of cargoes) provides the mandatory basis for the IMSBC Code.
• · IMDG Code — the parallel code for packaged dangerous goods.

Last verified 4 months ago